1. Field of the Invention
This invention relates to an apparatus and method for forming or casting prosthesis or prosthetic sockets on residual limbs.
2. Background of Related Art
Residual limb sockets are formed in accordance with the prior art using various apparatus and methods, including molding thermosetting, thermoforming or other resinous materials to obtain a relatively rigid socket for connecting a residual limb to a prosthesis device without discomfort to the user. Such molded sockets without and with reinforcements are exemplified in U.S. Pat. Nos. 5,163,965, granted Nov. 17, 1992, to Rasmusson and Fischel; and 5,263,990, granted Nov. 23, 1993, to Handal.
Prior art techniques include molding sockets of resinous materials using a male or positive mold of the residual limb that is formed from a plaster of paris female or negative casting sleeve that has been formed by molding the sleeve directly on the residual limb. It is also known to form the definitive socket using a pressure casting system exemplified by the ICECAST.RTM. system made by Ossur HF of Reykjavik, Iceland. The positive mold is then adjusted or "rectified" in accordance with well known techniques to provide relief for sensitive areas of the residual limb and to obtain a correctly sized socket that will properly fit the residual limb.
Other procedures for molding interim or definitive sockets have been described in the prior art, including a procedure whereby SCOTCHCAST.RTM. tape made by 3M Company of Minneapolis, Minn. has been utilized to produce an interim prosthesis socket for below-knee amputees.
Existing apparatus for forming prosthetic sockets on residual limbs tend to be bulky and somewhat complex. It is desirable to provide a simplified and compact prosthesis socket casting or forming system that not only facilitates pressure casting or molding of prosthesis socket or molding material directly on the distal end area of a residual limb but which also enables tension to be applied to the distal end area of the residual limb during the casting process to produce a better fitting socket.